Systems for injecting coiled tubing (CT) into and out of a well bore are well known, typically used for hydraulic fracturing operations. The majority of the known systems comprise an all-in-one trailer for supporting and positioning a coiled tubing injector supported in a mast, a coiled tubing reel and a control cab. The mast is erectable at a back end of the trailer over a wellhead, the reel being centrally located and the control cab located over the pin end of the trailer. The injector includes a gooseneck for guiding the coiled tubing into the injector from the reel. Drawworks, crown sheaves and cables position the injector and gooseneck in the mast at injection elevation. During running in and tripping out, CT is spooled on and off of the reel under control of an operator in the control cab. The CT can remain stabbed into the injector even during shipping.
Downhole operations demand longer and longer bottom hole assemblies (BHA's) which require longer/taller lubricators and require positioning of the injectors at a greater overall height or elevation above the wellhead. Further, as wellbores become longer and longer for maximizing access to deeper hydrocarbon payzones, the longer lengths of CT require larger reels, resulting in combined reel and trailer weights being greater than weight allowances and negatively affect dimensions of CT permitted for conventional transport.
More frequently, current systems are limited in regards to maximum injector elevation due to constraints upon limitations on the transportable length of the mast and the weight of the rig. Thus, a length of CT that can be carried with the rig is limited to accommodate transport or road allowances.
When masts are fit with deployable extensions, operations or length are compromised due to the difficulty in creating a continuous track through the extension, upon which the injector is to be raised and lowered.
Thus, there is interest in apparatus and methods for increased mast height for handling longer BHA's and for maximizing reel capacity while retaining the ability for meeting conventional road allowance requirements.